Treatment of hydrocarbons



June 19, 1934. E. ELLSBERG TREATMENT OF HYDROCARBONS Filed Dec. 27, 1930Zjrvuantoc s am/.4 am

Patented June 19, 1934 PATENT nsane FFECE TREATMENT or HYDROCARBONSEdward Ellsberg, Westfield, N. 3., assignor of three-fourths to TideWater Oil Company, Bayonne, N. J., a corporation of New JerseyApplication December 27, 1930, Serial No. 505,027

3 Claims.

In the well-known Edeleanu process of treating mineral oils with liquidsulfur dioxid to remove constituents which are unstable or are otherwiseundesirable, it has been necessary to provide means for continuallydrying the sulfur dioxid, since the latter takes up any water present inthe oil, with the result, were it not for the dryingof the sulfurdioxid, that water would accumulate in the system to the detriment ofthe apparatus besides necessitating interruption of the operation.Special difficulty has been encountered in this respect in the treatmentof lubricating oils. In purifying such distillates by the Edeleanuprocess I have found that it is imperative, or at least necessary inorder to avoid heavy expense, that the oil be practically chemicallydry. I have, therefore, sought to find a way of making the liquid sulfurdioxid process practical for the treatment of distillates of thisdescription, that is to say, finished or semi-finished oils heavier ormore viscous than kerosene and containing no, or substantially no,low-boiling fractions.

Such oils may be expected to contain small fractions of water running upto six-tenths of one percent, 0.4%-0.5% being ordinary. The removal ofsmall residual moisture contents from these hydrocarbon distillates is aspecial problem. There' are various processes for separat- 301mg thebulk of water from crude oil and the like containing much water, fortreating emulsions, and for taking off both water and light hydrocarbonfractions from material on the order" of crude oil, but such processesdeal with different material than thosewith which this invention isconcerned, and they do not produce a truly dry oil.

In the case of distillates such as motor and other lubricating oils,turbine oils, transformer *1'0115, cable oils andthe like, containingresidual moisture, or moisture absorbed from the air, the generalpractice, whenever a fairly dry oil has bee'n'requiredjthat is to sayone having no more than about 0.4% water or less, has been to heat 45,the 011' in a tank by means of steam coils while blowing air through thebody of the oil. This operation requires ten to thirty hours of time,the oil is frequently oxidized and injured by the heat and by the actionof the air, and the at- 501tainment of any exacting degree of dryness isnot only difiicult but uncertain. The moisture in the air is oftensufficient to defeat the operation, and for lubricating oil which shouldnot contain more than about 0.1% moisture when 55, shipped, it is 'oftennecessary to defer drying until a day when the atmosphere issufficiently low in humidity. I appreciate that quicker modes of dryingdistillates have been proposed, but as far as I am aware they have notbeen used, or used to any general extent, notwithstanding the great'need for a fast and efifective method of drying distillates such asthose contemplated in this application. It seems probable, therefore,that such methods either proved to be inefificient or unduly expensiveor that they resulted in injury to the distillates, which when finishedor partly finished are susceptible of de dried is immediately cooled andthen treated with remove the undeliquid sulfur dioxid to sirablehydrocarbons. Theentire process is carried on continuously without atany time heating the oil to a temperature greater than about Theaccompanying drawing illustrates schematically an apparatus for carryingthe invention into effect.

The distillate, which may be of a viscosity ranging from 40 seconds atF., Saybolt Universal,

to or seconds at 210 F., Saybolt Universal,

and which has a moisture content usually not over 0.6%, is fed by a pump2 through a line 3 to a heat-exchanger ,4, where it is partially heated,as for example to about 130 F. Thence it passes througha connection 5 toa heat-exchangeryor other heater, 6, where it is heated in transit, preferably to about F. to 200 F. 7 is a line for conducting exhaust steam orother heating-fluid to the heat-exchanger 6, to bring the temperature ofthe oil up to the required moderate degree without heating itsufficiently to causeinjury, and 8 is a discharge line for theheatingfiuid'or water of condensation.

'The heated oil proceeds from the heater 6 through a line 9 to a vacuumchamber 10. This is preferably an upright tower or tank containingbafiles 11 over which the oil admitted at 12 flows downward in a shallowstream or film. Upper bafiles lS'may be provided for restraining anyparticles or vapors of the oil which might otherwise escape through thetop exit 14 connected with vacuum line 15. Instead of flowing the 'oilover baffles in the vacuum chamber, it may be attenuated by spraying itinto the chamber, it being a desideratum to liberate the water vaporfreely from the more or less viscous material without requiring it tostruggle through any substantial bulk of oil.

The dried oil is withdrawn from the moderate sized body 1 6 whichcollects in the bottom of the vacuumizer, either by gravity if the tankis set, high enough, or preferably by a pump 17 which causes the driedoil to flow through a line 18 to the heat-exchanger 4, where it iscooled by exchange with the oil to be treated, preferably to being toowell known to require illustration-and description. The Edeleanuapparatus includes a cooler or coolers for the feed oil and consequentlythe cooler 20 need not chillthe oil to the final;

temperature required for that treatment.

Thewater vapor liberated from the oil in the vacuum chamber 10 iswithdrawn, and the-vac-- uum is maintained, preferably by a barometric rjet condenser 24 connected with the vacuum line 15., this condenserbeing proportioned andf-dea signed to create a vacuum in the chamberupwards of about 26 inches-of mercury A water line Z'Ssupplies Wamr tothe body of the condenser, and a steam line 31 supplies steam jets atthe top of the condenser and ma branch 26 of the condenser. The watervapor is condensed in the body of the condenser and passes with thewaterof the top water jet down through the limb 27 0f the, condenser toa collector 28, fromwhich the water may be conducted through a pipe 29to a sewer. The non-condensable hydrocarbon vapor or gas present, whichmight tend to accumulate and adversely affect the vacuum, is entrainedby the steam jets in the branch 26. and carried through a 1ine 30 whichmay connect with the discharge line 29. It will be understood, however,that the barometric condenser illustrated is only one form of means formaintaining the vacuum in the chamber 10, andthat any pumping equipment.capable of maintainingthe requisite vacuum mime used instead.

The. employment of a comparatively high vacuum is essential to reducethetemperature which is required to expelthe water as vapor from theoil. I have. ascertained that it is necessary to heat the oil to atemperature about 40 F. abovev the theoretical boiling point. atthe'absolute pressure inthe. chamber, this differential beingillustrative sin'ceit may be varied for different de grees of; vacuumand for different materials. On

the other hand the temperature of the oil should not be allowed to goabove about 200 F. for the average oil. Temperatures much above thathave.

' deleterious effect upon the color, flash-point or lubricatingqualities of the. oil.v Even atthese moderate temperatures it highlydesirable that the oilbe heated, dried and cooled, r pidly thisjprocess,the entire sequence of, these opera? tions. canbe. performedin less thanone minute,

to be a limitation, it is important, to keep the material ata moderatetemperature for only a short'penod; r

Within limits. on the orderof. those indicated. herein the temperatureand vacuum conditions are correlatively variable, and they maybe variedalso in accordance with the particular materials to be treated. Forefiective. and satisfac'.

tory results it is desirable that the vacuum be. upwards of about 26inches of mercury. If I the" moisture, but substantially-no low-boilinghydroture but substantially no low-boilinghydroeare vacuum is notsufficiently high the; oil will not be adequately dried even though;thev temperature be raised :to a pointat which injury to .lthe oil is.likelyto result. Asa preliminary treatment in the Edel'eanu. process itis of the greatest importance that these, oils be rendered practicallychemically dry, so that any moisture remaining is less than aboutoneone-hundredth of one per .cent. This is accomplished by the process,as is illustrated by the following example:

A medium motor oil having a viscosity of 300 seconds atl00 F., SayboltUniversal, is dried to 0.005% remaining moisture at a temperature of 180F, and a vacuum corresponding to'28 inches of mercury;

Theinvention maybe applied to the drying of finished or semi-finishedoils refined by different methods, and in such casesthe drying may beless thorough. V Y a it will be understood that modifications in the.process and in the apparatusare permissible and that the language usedin the following claims is intended to cover all-the generic andspecific novelty of the invention, and all statements-of, the scope ofthe invention which as ,a matter of 109; language might be said to fallbetween, the claims;

I claim: '1. The process of treatin lubricating oils or; other mineraloil distillates which ,contain carbon fractions, which comprises quicklyheating such distillate and subjecting -it. .to.:a;vac uum, the combinedconditions of temperature and vacuum being such that the moisture inthe, oil is. eliminated and the oil is dried to belowi 1 0.01% moistureWithout heating the oilat any .timetoatemperature aboveabout 2.00?:

, 2. The process of treating lubricating oils 6r} other mineraloildistillates which contain moisbon fractions, which comprises.quicklyheating such distillate and subjectingitto a. vacuum, the

ccrnh ed conditionsaoftemperature and. vac.-

uum eing such that themoisture in the-oil is: eliminated .and the. oilis dried tocbelow 0.01%.

. s ur wi o the t ;t .e. .9 .-a ermine $92 -a temperature above about200 Rand quickly; pooling the dried oil, the entireoperationpi-heating,drying andcooling each portion of the. oil] being performed in a periodnotsubstantially in excess of one minute, so. that the-timeduringx whichthe oil remains heated isasshcrtaspessiblelandne deterioration oi theualities; cf the oil occurs. 2 lg) 3.'The-process of removing smallfractions oh-13g. water from lubricating oils or, other mineraloil:distillates whichcontain substantially no low,-

boiling hydrocarbon fractions, which c rnprises], quickly heeting; suchdistillate; Lucid Frying the same b-y subjectingitto afvaeuum not lessor more above the boiling'point of Water at the not exceeding about 200F.-'.,;the combined-cor ditions; of temperature and vacuum beingsuch oilis dried below 0.01% moisture without -heating the oil atany. timeto atemperature abovev about 200" FL, and quickly cooling the drieddistillate. V

. EDWARD LLsB-ERG.

than about 26;1nchesv of merctu z' ihetemperaey and wliile so brief atime as. that is not intended.v inure to which the oil is heatedbeingabout 49 F. I

